Method of assembling multi-wall bulk pak shipping containers



y 1962 E. F. REPKING 3,041,942

METHOD OF ASSEMBLING MULTI-WALL BULK PAK SHIPPING CONTAINERS Filed Sept. 15, 1958 4 Sheets-Sheet 1 Jul 3, 1962 E. F. REPKING METHOD OF ASSEMBLING MULTI-WALL BULK FAK SHIPPING CONTAINERS 4 Sheets-Sheet 2 Filed Sept. 15, 1958 FIGS FIG]

July 3, 1962 E. F. REPKING METHOD OF ASSEMBLING MUL'II-WALL BULK PAK SHIPPING CONTAINERS Filed Sept. 15, 1958' 4 Sheets-Sheet 4 UVKE/Vfdt E0 WARD E REP/(ms Patented July 3, 1962 3,041,942 METHOD OF ASSEMBLING MULTI-WALL BULK PAK SHIPPING CONTAINERS Edward F. Repiring, Glasgow, M0., assignor to Crown Zellerbach Corporation, San Francisco, Calif., a corporation of Nevada Filed Sept. 15, 1958, Ser. No. 761,263 3 Claims. (Cl. 93-36.01)

This application contains subject matter common to copending application Serial No. 682,027, filed September 4, 1957, now abandoned entitled, Irreversible Inside Drum Pak Closure, inventor, Edward F. Repking.

The invention relates to an improvement in multi-wall containers such as, for example, large drum-like containers constructed of paperboard or other suitable bendable material, for packaging bulk commodities which is simple in construction, economical in material, particularly easy to assemble, has means located wholly within the container for automatically and permanently locking the cover members in place, requiring no special tools or other extrinsic devices for application, the container providing a substantial improvement in compressive and other strength properties.

The means for permanently locking the top and bottom closures to the body member of the container comprises the joint cooperation of three essentials of the container namely, (1) inwardly folded flaps integral with the top and bottom edges of the outer sleeve, (2) reversely folded locking flaps fixed to the outer face of flanges hinged to side edges of the top and bottom closure panels, in the folded position conforming to the contour of the inner face of the outer sleeve, positioned between the top and bottom end margins of the body member sleeves, and (3) the length of the inner sleeve fixed to correspond to the critical distance between the inner faces of the end closure panels when they are separated by the maximum distance that just efiects automatic end to end abutting engagement of the free ends of the outer sleeve flaps (1 above) with the free ends of the locking flaps (2 above) of the cover flanges, whereby the end edges (3 above) of the inner sleeve abut the inner faces of the cover panels and maintain the cover members permanently locked in fixed relation to the body member sleeves.

The distance between the free end edges of the top and bottom closure flange locking flaps and the fold at the end edges of the outer sleeve is very slightly greater than the length of the outer sleeve inturned flaps to permit the said free end edges of the closure flange locking flaps to snap into abutment with the free end edges of the outer sleeve flaps with the inner faces of the closure panels abutting the end edges of the inner sleeve.

The containers may be square, hexagonal, octagonal, etc. in shape. The hexagonal form is generally preferred.

Typical dimensions of the drums for packaging 200 to 400 pounds of material are: 30 gal. capacity, 17 inches between opposed wall panels commonly denoted as 17" x 17", 28 inches in height; 60 gal. capacity, 20 x 20 inches, 41 inches in height, etc.

The container of the invention embodies many practical advantages, it may be assembled easily and rapidly by a single operator without the use of tools or other extrinsic devices. The entire exterior surface of the container is free from all outward projections, thereby conserving storage space and providing maximum printing area. It has a high top load rating as well as other desirable strength properties, strapping is not required, the seal between the covers and sleeves is sift proof. The construction is pilfer proof since access to the interior is unobtainable without obvious mutilation of the container. The saving in cost of the drum over presently available drums of comparable quality, reliability and function is substantial. The outward thrust of flowable bulk contents such as materials in powder, granular or pellet form and other materials tend to hold the locking means even more securely together.

An object of the invention is to provide a container having a body member of telescoped inner and outer open ended sleeves with closure members permanently locked to the body member by means located entirely within the container.

Another object of the invention is to provide generally a sift proof, pilfer proof multi-panel container comprising inner and outer telescoped sleeves with cover panels conforming in contour to a horizontal cross section through the inner faces of the outer sleeve. The cover panels are permanently locked to the outer sleeve with their outer faces in substantially the plane of the folds at the ends of the outer sleeve by automatic locking engagement of flaps located between the top and bottom margins of the sleeves, with the inner faces of the cover panels in abutment with the respective top and bottom edges of the inner sleeves.

Still another object is to provide a container having a body of open ended telescoped sleeves with closure members immobilized in permanently fixed locked relation to each other and to said sleeves by the joint combination of (l) inwardly folded flaps hinged to the top and bottom ends of the outer sleeve, (2) reversely folded locking flaps fixed to the outer face of inwardly folded flanges hinged to the side edges of the closure panels, and (3) the length of the inner sleeve fixed to correspond to the critical distance between the inner faces of the closure panels when they are separated by the maximum distance that just permits automatic end to end abutment of the said outer sleeve flaps with the said cover panel flange locking flaps, whereby the end edges of the inner sleeve abut the inner faces of the cover panels and maintain the closure members permanently locked in fixed relation to the body member.

Another object is to provide a method for assembling the blanks for forming a container body member having telescoped inner and outer open ended sleeves and closure members permanently secured to the body member. The method comprises assembling the bottom closure member and telescoping the outer sleeve thereover, collapsing the inner sleeve inwardly and inserting it Within the outer sleeve until its bottom edges are in abutment with the inner face of the bottom closure panel. 'I'hen restoring the inner sleeve to its normal polygonal shape and inserting the top closure member flanges and locking flaps between the inner and outer sleeves until said locking flaps snap into end to end abutment, with the inner faces of the closure panels in abutment with the end edges of the inner sleeve.

The invention also consists in the parts, arrangement and combination of parts hereinafter described and claimed and the accompanying drawings form a part of this specification and like numerals and symbols therein appearing refer to like parts wherever they occur.

In the drawings:

FIG. 1 is a plan view of the blanks of the component parts of the container;

\ FIG. 2 is a perspective view of the assembled outer sleeve blank A with integral top and bottom end flaps turned inwardly;

FIG. 3 is a perspective view of the inner and outer telescoped sleeves with a bottom pad in place;

FIG. 4 is a perspective view of the assembled inner and outer sleeves with the bottom closure partially inserted within end margins of the sleeves, with reinforcing pads in place and a portion cut away to illustrate the relation of parts and with the assembled top closure pre- J paratory to insertion within the end margins of the con tainers sleeves;

FIG. is a perspective view of the full assembled container;

FIG. 6 is a vertical section of the assembled container with an end closure member in process of insertion between the sleeves with pad in place;

FIG. 7 is a vertical sectional view taken in the direction of arrows 77 of FIG. 5 illustrating the relation of parts in an end closure of the completely assembled container;

FIG. 8 is a plan view of the blank of the outer sleeve of a modified form of the container showing the reinforcing tape and tear tape;

FIG. 9 is a vertical section of the blank of FIG. 8 taken in the direction of the arrows 9.);

FIG. 10 is a vertical section of the blank of FIG. 8 taken in the direction of the arrows 1010;

FIG. 11 is a perspective view of the partially assembled blank of FIG. 8;

FIG. 12 is a horizontal section of FIG. 11 taken through the folded top infolded locking flaps;

FIG. 13 is a plan View of the blank of one of the closure members of the container;

FIG. 14 is a perspective view of the fully assembled blank of FIG. 13;

FIG. 15 is a perspective view of the assembled outer sleeve and bottom closure blank with a portion broken away to illustrate the position of the bottom closure flanges and flaps;

FIG. 16 is a prospective view showing the inner sleeve inwardly collapsed prior to insertion Within the outer sleeve, the dotted line indicating the normal position of the inner sleeve;

FIG. 17 is an enlarged fragmentary elevation of the bottom portion of the assembled outer sleeve and bottom closure members with a portion cut away, showing the bottom ends of the collapsed inner sleeve in abutting relation to the end closure panel;

FIG. 18 is a perspective view of the partially assembled container with the inner sleeve in normal position and the dotted lines indicating the partially collapsed condition which allowed insertion within the outer sleeve;

FIG. 19 is a section of the container fully loaded and prior to insertion of top closure member, taken in the direction of the arrows 1919 of FIG. 18;

FIG. 20 is a vertical section of the container of FIG. 19 showing the top member in process of insertion into locking position;

FIG. 21 is a vertical section of an upper corner of the fully assembled container showing a pad inserted between the closure panel and the end of the inner sleeve with a crushed marginal portion of the pad resting on the top edge of the inner sleeve.

In the blank A, FIG. 1, of the outer sleeve, transverse scores 11 and longitudinal scores 12 define wall panels 10 and hinge lines of top and bottom flaps 13 and 14 separated at least in part at their side edges by slots 15, said flaps having free end edges 17. A securing flap 16 which is coextensive in length and attached to the outer edges of the outer panel 10 is also defined by score 11.

The blank B for forming the inner sleeve is scored transversely at 21 to define the side walls 20 and securing flap 22, coextensive in length therewith.

The closure blanks C are scored at 26 to define the closure panel with side edges corresponding in numbet and essentially coextensive in width with the Width of the panels of sleeves A and B. This score also defines the hinge lines of flanges 27 which have locking flaps 29 hinged to their outer end edges defined by scores 28, said locking flaps have free end edges 30. Pad D consists of fiat sheet corresponding in contour to the panels 25 of the cover members. The use of this pad is optional but may be employed to advantage in packaging relatively large quantities of heavy material.

The margins of the 4 pad are normally crushed at 35b as shown in FIG. 21 to facilitate sift proof closures of the container.

FIG. 2 is a perspective view E of the erected outer sleeve A with sealing flaps 16 attached to the opposite remote panel 1%) by staples, glue or other suitable means. The top and bottom outer sleeve flaps 13 and 14 respectively are folded inwardly adjacent the upper and lower inner margins of the outer sleeve.

The perspective view F of FIG. 3 illustrates the container with a bottom pad 35 inserted in the bottom of the container and the inner sleeve B telescoped within the outer sleeve A and with the outer top and bottom flaps 13 and 14 respectively juxtaposed between the upper and lower margins of the sleeves. The top pad 35 is here shown ready to be inserted over the top edges of the inner sleeve B.

The perspective view of FIG. 4 shows a further step of the assembly wherein the top pad 35 is inserted within the outer sleeve turned down flaps and resting on the top end edges of the inner sleeve. This figure also shows the bottom closure member partially in place and the top closure member fully assembled ready to insert the cover flanges 27 between the outer sleeve flaps 13 and the inner sleeve until the top panel 25 rests on the pad 35 and the free end edges of the flange flaps 29 are snapped into abutting relation with the free end edges 17 of the outer sleeve turned down flaps 13. The pad 35 may be carried by the cover member and then associated with the container as hcreinbefore described. The completely assembled container is shown in the perspective View, FIG. 5.

The vertical sectional view of FIG. 6 shows the flanges 27 and flaps 29 in the process of insertion between the flaps 13 of the outer sleeve 10 and the inner sleeve 29.

The cover member in place is shown in the vertical sectional view of FIG. 7, the outer face of the panel 25 being in substantially the plane of the top folds 40 of the outer sleeve with its underface resting on the top pad 35 and the free end edges 17 of the flaps 13 abutting free end edges 30 of the reversely folded flange flaps 29 of the cover member.

The distance between the cover panel 25 and the pad 35 of the sectional view FIG. 7, is exaggerated to clearly distinguish these members from each other; actually the panel 25 is in flatwise contact with the pad 35, when the pad is employed, or in the absence of the pad it will be in contact with the upper edges 23 of the inner sleeve.

The container E, FIG. 2, may be assembled in any convenient manner. A preferred method is to fold panels III of the blank A carrying the securing strip 16 over the other panels and securing the strip 16 to the outer vertical margin of the remote panel 10. The panels 2d of blank B are similarly folded and attached together by the securing strip 22 in the same manner as described for the outer sleeve A.

The outer sleeve is next opened into tubular form and the top and bottom flaps 13 and 14- respectively folded inwardly as shown in FIGS. 2 and 3, forming the broad top and bottom folds 40. The inner sleeve B is then inserted within the outer sleeve A as shown at F, in FIG. 3, the flaps '13 and 14 being positioned between the upper and lower margins of the telescoped sleeves.

The cover members C may be assembled by folding the locking flaps 29 reversely about the scores 28 into flatwise engagement with the outer face of flanges 27. The flanges are then folded downwardly to approximately the position shown in FIG. 4.

It should be noted from FIG. 7 that the distance between the flap fold 40 of the outer sleeve A and the free upturned edges 30 of the locking flaps 29 is slightly greater than the length of the body flaps 13 from the top fold 44) to the downturned free end edges 17 so that the end edges 30 of fiaps 29 automatically fall into aligned abutting relation with the downturned free end edges 17 of the outer sleeve flaps 13 when the cover flanges 27 are inserted between the upper margins of the sleeves A and B. At this point the cover panels 25 will be within the upper and lower margins of the outer sleeve inwardly folded flaps 13 and 14 respectively, with their inner faces resting on or engaging the upper and lower end edges 23 of the inner sleeve B, or the edges 23 engaging the adjacent marginal portions of the pad 35 or 35a and thus precluding further inward movement of the cover panels 25 from substantially the plane of the top and bottom folds 40 of the outer sleeve A.

The length of the cover panel flanges 27 and their reversely folded locking flaps 29 and the length of the outer sleeve flaps 13 may be varied if desired, contingent upon maintaining the hereinbefore described distance relations. For example, in a relatively large container for packing large quantities of a relatively heavy material, it may be desirable to have the outer sleeve flap 13 four inches (4) or more in length with a corresponding adjustment of the length of the cover flanges 27 to meet the aforesaid required distance relation between the abutting or engaging end edges 17 and 30 of the respective flaps 13 and 29. Conversely, the length of the outer sleeve flaps 13 may be reduced to one and one-half inches 1 /2") for example, for packing smaller quantities of material while maintaining the hereinbefore mentioned distance relations.

A modified form of the invention is illustrated in FIGS. 8 to 21 inclusive.

A plan view of the blank which forms the outer sleeve of the modified form is shown at 50, FIG. 8. The longitudinal scores 51 and 52 define the end edges of the body panels 56 and the hinge lines of the top flaps 57, 58, 59, 6t), 61 and 62 and the hinge lines of bottom flaps 65, 66, 67, 68, 69 and 70. The transverse scores 53 define the hinge lines connecting the panels 56 and the glue flap 55. Top flaps 58 and 59 are separated on their side edges by slot 63 and flaps 60 and 61 by slot 64 while the bottom flaps 66 and 67 are separated by slot 71, and 68 and 69 by slot 72. A portion of the outer liner 77 of the blank is broken away to show the direction of the flutes 73 of the corrugated medium and the position of a reinforcing band 74 extending longitudinally between the corrugated medium and the outer liner 76. The blank is also cut away to show a longitudinal tear strip 75 positioned on the outer face of the inner liner 77.

A longitudinal sectional view of the blank of FIG. 8 is shown in FIG. 9 taken in the direction of the arrows 99, the tear strip 75 being on the outer face of the inner liner 77. FIG. is also a longitudinal sectional view of the blank of FIG. 8 taken in the direction of the arrows 10-40 showing the reinforcing band 74 positioned between the outer liner 76 and the corrugated medium 73.

The inner sleeve blank of the modified form of the invention is substantially the same as the blank B of FIG. 1, transversely scored at 21 to define side walls and the securing flap 22.

A perspective view of the outer sleeve assembled into polygonal form from the blank of FIG. 8 is illustrated in FIG. 11, wherein one of the end panels 56 is secured by the glue flap 55 to the other end panel and the top flaps 57 to 62 inclusive are folded inwardly and downwardly adjacent the inner face of the outer sleeve side walls. The drawing also shows the initial position of these top flaps before folding in dotted lines and also the tear strip 75 on the inner face of the inner liner encircling the container at an appreciable distance below the free end edges of the inner sleeve. This drawing also shows the inwardly folded bottom flaps 65 to 70 inclusive in dotted lines.

It will be noted that the flaps 58 and 59 separated by slot 63 and flaps 61) and 61 by slot 6 with the opposite side edges of the flaps being scored to the longitudinal score 51 to define said flaps. The flaps may be readily folded downwardly against the inner face of the body walls of the container and become automatically locked in this position when the sleeve is in tubular form without the use of staples, glue or other securing means. The same process of locking the flaps in position applies to the bottom flaps 65 to 70 inclusive. FIG. 12 is a horizontal section through the folded outer sleeve flaps of the container of FIG. 11 showing the locked flaps enclosing the reinforcing band 74.

FIG. 13 shows a plan view 78 of the blanks for forming the top and bottom closures. The cover panel '79 which corresponds in contour to the end of the inner face of the outer sleeve of the container is defined by scores 79a which are also the hinge lines of cover flanges 80. The outer edges of the flanges are defined by the scores 80a which are also the hinge lines of locking flaps 81. The cover flanges are separated on their side edges by slots or cutout portions 82.

The top and bottom closure members are: assembled by reversely folding the locking flaps 81 in flatwise relation to the outer face of the flanges 80 and then folding the flanges substantially right angularly inwardly with respect to the inner face of the closure panel 79. FIG. 14 is a perspective view of the closures assembled as described. The reversely folded locking flaps 81 may be secured to the outer face 80 of the cover panel flanges by staples 93 as indicated, or by glue or other suitable means.

FIG. 15 is a perspective view illustrating the first step of assembling the container proper. The outer sleeve A" with its infolded bottom flaps 65 to 70 inclusive is telescoped over the bottom closure (assembled. as in FIG. 14) until the free end edges 69 of the infolded bottom flaps snap into end to end abutment with the free end edges of the bottom closure locking flaps 81. A

portion of the lower part of FIG. 15 is broken away.

to clearly illustrate the relation of parts at this stage of the assembly.

The first stage of the operation of telescoping the inner sleeve B within the outer sleeve A" is shown in the perspective view FIG. 16, wherein a pair of connected together side panels of the inner sleeve B" are inwardly collapsed which permits the sleeve to be readily positioned with its bottom end edges in abutment with the bottom closure panel 79 and at least one of its wall panels 84 in flatwise relation to the inner face of the closure flanges 80. FIG. 17 is a somewhat enlarged fragmentary elevation of the lower portion of the container with the inner sleeve collapsed and in position as described. The full length perspective view of FIG. 18 of the container shows the inner sleeve restored to its normal hexagonal position from the collapsed dotted line position with all of its panels in closely parallel relation to the corresponding panels of the outer sleeve and the lower margins of all of its wall panels in flatwise firm, fixed, gripping engagement or contact with the inner face of closure panel flanges 80.

After the inner sleeve has been restored to its normal form within the outer sleeve, the container is loaded with flowable or other type or kinds of materials as indicated in the vertical sectional view of FIG. 19. The loaded container is now ready for the application of the top closure. The process of inserting the top closure is shown in the vertical section FIG. 20, wherein the flanges 8t) of the cover panels 79 with their reversely folded upturned locking flaps 81 are being inserted between the top margins of the inner sleeve panels 84 and the inturned flaps 57 to 60 inclusive of the outer sleeve A". In the final position of the closures, the innerfaces of the top and bottom cover panels 79 abut the top and bottom edges 85 respectively of the inner sleeve and the free end edges of the locking flaps 81 are in end to end abutment with the free end edges of the inturned outer sleeve flaps 57 to 60 inclusive, permanently immo- 7 bilizing all parts of the container in fixed relation to each other. The upper marginal portion of the inner sleeve B" is also in firm, fixed, gripping engagement or contact with the innerfaces of the closure panel flanges 80 whereby relative movement between the inner and outer sleeve is prevented.

When top and bottom pads 35a are employed, the collapsed or crushed side margins of the pads will be interposed between the end edges of the inner sleeve panels 85 and the innerface of the closure panels 79 as illustrated in the ver 'cal sectional View of FIG. 21, forming a substantially incompressible closure of the panel 79 and the top edges of the inner sleeve panels 35.

The loaded container described is pilfer proof as well as sift proof. All parts of the container are permanently locked in fixed position, consequently access to the interior thereof is precluded without visual evidence of tampering or mutilation. The reinforcing band 74, positioned in close proximity to the top flap hinge line 51 of the outer sleeve Wall panels, elfectually prevents tearing or disruption of the package if and when the loaded container is carelessly dropped on a corner, for example in the course of handling and transportation. If desired a reinforcing band may be similarly placed in close proximity to the bottom hinge line 52 of the outer sleeve wall panels. For convenience at the point of use the tear strip 75 (shown in process of operation, FIG. 18) permits the upper portion of the outer sleeve with attached closure member to be lifted from its telescoping relation with the inner sleeve for access to the contents and forms a replaceable cover telescoping the upper margin of the inner sleeve.

The permanent locking of all parts of the loaded container in fixed position permits the container to be handled on its side, upturned or in any other position without danger of damage or loss of contents.

It is understood that the particular embodiment of the invention described is illustrative and not restrictive. The invention may be susceptible of embodiment in other modified forms. All modifications which are similar or equivalent hereto come equally Within the scope of the claims next appearing.

In the claims:

1. The method of erecting a polygonal tubular container comprising the steps of positioning a flanged bottom end closure member in one end of an outer sleeve, collapsing inwardly two adjacent wall panels of an inner sleeve about their common fold line, inserting the collapsed sleeve within the outer sleeve until one end thereof comes into abutting relation with the inner surface of the prepositioned end closure, expanding the inner sleeve into tubular form conforming to the interior of the outer sleeve, deflecting the top end portions of the inner and outer sleeve laterally into spaced relation while inserting flange parts of a top end closure member therebetween.

2. The method of erecting a polygonal tubular container having inner and outer telescoping sleeve members and an interiorly locked end closure comprising the steps of erecting the outer sleeve to open ended tubular relation, infolding top and bottom flaps thereof into flatwise relation With respective interior end marginal portions, positioning a closure panel in one end of the sleeve and directing locking flanges thereabout inwardly of the sleeve, erecting an inner sleeve member to tubular relation and partially collapsing the same by inwardly directing adjacent portions thereof, inserting the inner sleeve Within the outer sleeve until its bottom end edges are in abutment with the inner face of the closure panel and urging the locking flanges of the closure panel in edgewise abutment with respective flaps of the outer sleeve, restoring the sleeve to polygonal form with Wall portions in parallel relation to the counterpart portions of the outer sleeve.

3. The method of erecting a polygonal tubular container having inner and outer telescoping sleeve members and interiorly locking end closures, comprising the steps of erecting the outer sleeve to open ended tubular relation, infolding top and bottom flaps thereof into flatwise relation with respective interior end marginal portions, positioning a closure in one end of the sleeve and directing locking flanges thereabout inwardly of the sleeve, erecting an inner sleeve member to tubular relation and partially collapsing the same by inwardly directing adjacent portions thereof, inserting the inner sleeve within the outer sleeve until its bottom end edges are in abutment with the inner face of the closure panel and urging the locking flanges of the closure panel in edgewise abutment with respective flaps of the outer sleeve, restoring the sleeve to polygonal form with wall portions in parallel relation to counterpart portions of the outer sleeve, deflecting top end portions of the inner and outer sleeve into spaced relation While inserting locking flange parts of a top closure therebetween, further inserting the top closure into abutment with the inner sleeve and locked engagement with said outer sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 1,284,196 Kondolf Nov. 5, 1918 2,075,679 Weber Mar. 30, 1937 2,308,050 Burr Jan. 12, 1943 2,404,067 Hill July 16, 1946 2,620,119 George Dec. 2, 1952 2,794,588 George et a1. June 4, 1957 2,808,190 Buhrmaster et a1. Oct. 1, 1957 2,902,202 Fallert Sept. 1, 1959 FOREIGN PATENTS 755,743 Great Britain Aug. 29, 1956 

